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Would you swap a packet of your old powder . . .

By ANDY COGHLAN

Consumers are doing the environment no favours when they buy ‘green’
washing powders, claims Bryn Jones, a former director of Greenpeace. Jones
investigated the environmental effects of every stage in the manufacture
and use of each type of powder, and concludes that ordinary powders, which
contain phosphates, do no more damage than phosphate-free powders.

‘When we looked at both products in a detailed analysis, there was
very little difference between them in terms of environmental impact,’
he says.

Environmentalists began to demand phosphate-free detergents in the mid-1980s
as evidence mounted that phosphorus was causing problems in Europe’s lakes
and rivers. Phosphate is a plant nutrient, and too much of it encourages
algal blooms. When the algae die, the bacteria that break down their tissues
consume the oxygen in the water. In extreme conditions the oxygen level
falls so low that animal life suffocates.

Jones, who left Greenpeace in 1986 and now runs Landbank, an environmental
consultancy in London, began to have doubts about green detergents two years
ago. ‘We thought the received truth on this was a bit dodgy,’ he says. Cynics
are likely to say this conclusion was inevitable, given the study was funded
by Albright & Wilson, a company that makes phosphate-based detergents.
Jones insists the study is impartial.

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The rationale for green detergents was that they would prevent discharges
of phosphate into rivers. But there are other environmental costs attached
to washing powders, earlier in the chain of production.

The main difference between traditional washing powders and green ones
lies in the ingredient known as a ‘builder’. Traditional builders, based
on phosphates, maintain the pH of the wash water at between 9 and 10, which
improves the action of other ingredients that dislodge dirt and stains.
They also help to prevent dissolved dirt from resettling on clothes. The
most common builder is sodium tripolyphosphate (STPP).

As demand for green products grew, some producers switched to an aluminium-based
material called zeolite A. Zeolites soften water, but cannot maintain pH
or prevent dirt from resettling on clothes, so a ‘co-builder’ called polycarboxylic
acid (PCA) had to be added.

Jones and Bob Wilson, his co-director at Landbank, have drawn up a league
table of penalty points for each builder, based on the way raw materials
are extracted and transported to the factory, the manufacturing process
and how ecologically damaging the detergent is once it reaches the river.

From this information, Jones calculated an environmental impact score
for 1 kilogram of each builder material. For both builders the biggest impact
comes from the carbon dioxide generated during processing and transport
of raw materials and manufacture. Phosphate earned a large proportion of
its penalty points at the mining stage; phosphate mines in Morocco discharge
large quantities of gypsum into the Atlantic, smothering the sea floor and
leaching toxic heavy metals into the water.

The most environmentally damaging stage in the manufacture of zeolite
builders is the opencast mining of Australian bauxite ore from which the
zeolite is made, and the carbon dioxide generated during transport of the
ore to Europe.

Tests showed that it takes 1 kilogram of a zeolite-PCA mixture to give
as good a wash as 0.7 kilograms of STPP. Taking this into account, STPP
earned 107 penalty points and the zeolite-PCA mixture 110, so there is little
to choose between them.

But Jones points out that there is more scope for reducing the pollution
from phosphate detergents. Phosphates can be extracted from waste water
before it is discharged into waterways, and the recycled phosphate used
to manufacture washing powders. This would wipe off 30 to 40 penalty points
from STPP’s score. There is no known way of recycling zeolites.

Jones would like to see devices called ‘crystalactors’ fitted to sewage
works. The crystalactor, developed in the Netherlands, extracts phosphate
from sewage, by far the largest source of phosphate pollution, and converts
it into pellets of calcium phosphate, which can be recycled.

Roisin Orisz of Ark, an organisation that markets green washing powders,
says: ‘We are trying to devise washing powders that dispense with both types
of builder, but we’re having difficulties with that.’